Every year, I always promise myself I shan’t grow onions again. They take up space, are a bit of bother, and invariably end up costing more to grow than they do from the local market.

Really, I’d rather use onion beds to grow costly and more unusual vegetables which taste epic when they are homegrown. I only have a small vegetable patch, and it seems silly to waste the space with onions.

But if you have more space than you need, and want to have all your veg homegrown, then the cheapest way to do so is to grow the onions from seed, not sets. And if you want to do that, you need to run into the garden today and get sowing.

I like to sow my onion seeds in mid-February, which is early enough for the plants to bulb up nicely by the end of the year, but late enough for the light to be a little stronger. I sow them in lines in seed trays in the heated propagator on my sunniest windowsill.

Within a couple of weeks, the little green hook-like seedlings are springing up. I tend to pot them on into fresh soil when they are an inch tall and still bent over, and plant out in April after hardening them off in a cold frame.

Onion soil can be a bit tricky. If you plant onions in super-fresh, super-rich soil, they will put on enthusiastic leafy growth at the expense of nice chunky bulbs. But give them weak, tired soil, and you’ll find they limp to a small, paltry crop. So I tend to plan my crop rotation so that onions grow in a bed used for tomatoes or pumpkins the year before. Those hungry fruiting vegetables will have received the gold service in feeding, and their soil will be marvellously rich. I also tend to dig in extra garden compost in late autumn so that it has broken down sufficiently by the time the onion seedlings go in.

Growing onions from seed means bolting (when the plant produces a flower spike early and forgets to swell its bulbs any further) is less of a problem. But if you do find a little flower head limbering up on any of your onion plants, snap it off quickly and make sure you use that onion first as a bolted onion won’t store well.

If you are growing onions for the first time, I would recommend ‘Bedfordshire Champion‘, as it has always performed well for me in the years I have succumbed to having onions in my veg patch.

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